PACKAGING FOR A BRAKE SYSTEM
An actuation device for a hydraulically operating brake system may include: a master cylinder in a housing and having at least one piston, to which a force can be applied by, e.g., a brake pedal; pressure supply device(s), at least one of which is a piston pump or double stroke piston pump having a piston and driven by an electromotive drive, the drive moving the piston directly or via a step-up gear; at least one valve assembly with magnetic valves; and at least one electronic control and regulating unit. The brake system has at least two hydraulic circuits, and a pressure change can be carried out in at least one wheel brake via the pressure supply device(s). A first housing or module, hydraulically connected to the housing, may contain the valve assembly and the at least one piston and pressure chamber of at least one of the pressure supply devices.
The present invention relates to an actuating system having the features of the preamble of claim 1.
PRIOR ARTThe packaging or structural volume of brake systems is of great importance. In particular in the case of systems with SAD (semi-automated) and FAD (fully automated driving), many variants from level 2 with tandem master brake cylinder (THZ) or single master brake cylinder (HZ) to level 5 without THZ or HZ must be taken into consideration. In particular, 3-5 concepts with 2 pressure supplies or pressure supply devices (DV) are difficult to implement in terms of packaging with a small construction volume. Examples of packaging are known from EP 2744691 with a vertical arrangement of the pressure supply (DV) with respect to the master brake cylinder (HZ) axis and DE 20160321161604 with a parallel arrangement of the pressure supply device with respect to the master brake cylinder (HZ) axis, which require a smaller structural width. Redundant pressure supplies allow systems with only one master brake cylinder, because the probability of failure of two pressure supply devices is very low and is practically limited to the failure of the on-board electrical system. Such a system is described in DE 102017222450. Here, the master brake cylinder HZ still allows emergency driving with the brake, for example to the towing vehicle.
DE102016105232 A1 has already disclosed a packaging with a small structural volume in the case of which an integrated redundant pressure supply composed of at least one pressure supply device, with valves, in particular solenoid valves combined in a hydraulic unit, with at least one electronic open-loop and closed-loop control unit, at least one reservoir, and a master brake cylinder is combined in one module.
OBJECT OF THE INVENTIONIt is the object of the present invention to provide modular packaging for various systems with a small structural volume.
Advantages of the InventionSaid object is achieved by means of a system having the features of claim 1. Advantageous configurations of the system as claimed in claim 1 result from the features of the subclaims.
A packaging with a small structural volume is proposed, having an integrated redundant pressure supply DV composed of at least one pressure supply device, with valves, in particular solenoid valves combined in a hydraulic unit, with at least one electronic open-loop and closed-loop control unit, at least one reservoir, with a single master brake cylinder and pedal stroke sensors and travel simulator with piston. The invention provides different variants of modular actuation systems for brake systems which comprise as many identical parts as possible for manufacturing and assembly.
Possible variants according to the invention are preferably:
Variant a:is a 2-box solution with two modules, wherein the first module comprises the pressure supply device (DV1), master brake cylinder (HZ) with travel simulator (WS), valve arrangement (HCU), open loop and closed-loop control unit (ECU) and reservoir (VB), and the second module comprises ESP or ABS,
Variant b:is a 1-box solution with only one module, which comprises at least one pressure supply device (DV1, DV2), the valve arrangement (HCU), open-loop and closed-loop control unit (ECU) and reservoir (VB),
Variant c:is a 1-box solution with only one module, which has the pressure supply device, wherein at least one pressure supply device is of redundant configuration, that is to say for example with a double on-board electrical system connection or redundant phase windings, and wherein the valve arrangement (HCU), open-loop and closed-loop control unit (ECU) and reservoir (VB) are likewise included in the module.
Variant d:the same module as with variant c., but with an open-loop and closed-loop control unit of fully or partially redundant configuration.
Variant e:is a 2-box solution with two modules, wherein the first module comprises a pressure supply device (DV1, DV2), valve arrangement (HCU), open-loop and closed-loop control unit (ECU) and reservoir (VB), wherein the open-loop and closed-loop control unit (ECU) is a fully or partially redundant configuration, and the second module comprises either the master brake cylinder (HZ) with optional travel simulator (WS).
Variant f:first module as in variant e, wherein, in the second module, instead of a master brake cylinder, there is or are arranged an electronic brake pedal with travel simulator WS or only a brake switch for level V.
The housings described below are advantageously used here. These housings form subassemblies which, when assembled, form the entire unit for installation into the vehicle:
Housing A: comprises the valve arrangement (HCU) for the pressure supply devices DV1 and DV2 with, for example, valves (V), solenoid valves (MV) and one or more pressure transducers (DG).
Housing B: comprises the open-loop and closed-loop control unit ECU without redundancy with a main plug connector or with partial or full redundancy with two plug connectors to the on-board electrical system.
Housing C: for master brake cylinder HZ with pedal stroke sensors and small sensor ECU and reservoir VB for variant e. The master brake cylinder HZ also comprises the pedal interface (PI) to the brake pedal and also the travel simulator with piston and spring.
The housing A (HCU) is preferably manufactured from an extruded molded piece, which is very highly suitable for fastening and assembly using calking technology. Here, the pressure supply DV1 with piston drive and ball-screw drive KGT is to be integrated with the motor, and likewise pressure supply DV2 with small piston pump of ABS/ESP, and furthermore the valves and solenoid valves. Here, pressure supply DV1 is arranged for example parallel to the master brake cylinder (HZ) axis, and the piston pump of pressure supply DV2 is arranged perpendicular to the pressure supply DV1. Aside from the pressure supply DV1, pressure supply DV2 corresponds to the proven technology of ABS/ESP, and it is thus inexpensive with a small structural volume. Alternatively, a gear or vane pump with continuous delivery action may be used. The interface to the open-loop and closed-loop control unit ECU is also similar to ABS/ESP. The master brake cylinder HZ with all of the abovementioned components (housing C) can be screwed to housing A—this applies to all variants except for variants e and f. Here, the housing C is mounted, as a subassembly separate from the unit, onto the bulkhead, and the hydraulic line from the master brake cylinder HZ is connected to housing A. In the variants a. and d., the reservoir VB is situated in the housing A with two connections to the brake circuits or with an additional connection to the pressure supply DV. The float in the reservoir VB comprises a target with a connection to the sensor element in the open-loop and closed-loop control unit ECU. The motor may preferably be connected to the housing A via an intermediate housing, which is preferably composed of plastic. The sensor required for commutation of the motor and piston position may preferably be attached to the motor housing on the side situated opposite the piston along the motor axis, and connected to the open-loop and closed-loop control unit ECU. Here, the sensor is situated in an additional housing in relation to the ECU. As redundancy for the electrical connection of the magnet coil of the solenoid valve, a small additional circuit board in relation to the main circuit board PCB may be used for a second connection of the magnet coil. The housing A may also be divided into a housing A1 for the pressure supply DV2 with a small pump and with the valve MV, as well as pressure transducers DG and other components, and a housing A2 for the pressure supply DV1 with motor and housing and piston with ball screw drive KGT and valves with connection to the reservoir VB.
The illustrated packaging meets the requirements for modularity and small structural volume and is also very inexpensive in terms of costs and weight.
Through the provision of a special sensor housing, it is possible for the manufacturing-related tolerances of the housing of the unit according to the invention to be easily compensated, such that the motor sensor can be reliably placed at the position intended for it.
Furthermore, owing to a special design of the reservoir, its filler neck or opening may advantageously be arranged on or in front of the front side of the housing of the electronic control unit or the actuating device, so as to be easily accessible. Owing to the connection, which leads laterally past the housing of the electronic control unit, of the front filler neck to the rear of the housing of the control unit, the reservoir itself can expediently be arranged behind the control unit. The lateral or central region of the reservoir can advantageously be designed to be narrow, such that the actuating device is hereby no wider, or only insignificantly wider, than in the case of a conventional reservoir.
Different variants will be discussed in more detail below on the basis of drawings.
In the drawings:
On the opposite side, the sensor housing 3 with the rotational angle sensor is connected both to motor 2 and ECU 18 via a preferably flexible circuit board (not illustrated) with the intermediate housing. Attached on the top side of the open-loop and closed-loop control unit ECU are the plug connectors, which are implemented twofold in the case of the redundant ECU. In the variant with separate master brake cylinder HZ, the corresponding connecting line to the master brake cylinder HZ is provided at 11. The reservoir VB may, in the conventional manner, comprise a level sensor (NS) with a float, wherein the target with the sensor element are arranged in the open-loop and closed-loop control unit ECU, which is preferably of redundant configuration in the case of levels 4 and 5. In the fully integrated version, the master brake cylinder HZ is arranged behind the valve arrangement block HCU, which master brake cylinder is screwed to the HCU block 24 by means of fastening screws 13.
Here, the axis of the pressure supply device DV1 lies parallel to the master brake cylinder (HZ) axis or approximately perpendicular to the flange and the axis of the pressure supply device DV2 is perpendicular to the axis of the pressure supply device DV1. The axis aDV2 of the piston of the pressure supply device DV2 may be both parallel to the axis aDV1 of the pressure supply device DV1 and rotationally offset at an angle α, which advantageously shortens the structural length. As a further alternative to the described arrangement of DV2, an arrangement of aDV2 parallel to the vertical axis may be used. In this case, a different installation location must be provided for the lower plug, for example on the opposite side of the open-loop and closed-loop control unit ECU.
The motor of the pressure supply device DV2 acts with, for example, an eccentric on the piston pump, as in the case of ABS/ESP. As is known, the structural space for this is very small. Alternatively, the motor may also drive a gear pump, which is of short construction. Arranged on the left-hand side is the ECU with housing 18 with main circuit board PCB 23, which is connected to the plug connector St situated at the top.
The solenoid valve (MV) coils are, via connecting webs 21, connected by means of press-fit contacts to the circuit board PCB 23 in the conventional manner. The connection of the connecting webs 21 to the coil wire is considered fail-safe owing to automated production with process control, but this does not necessarily apply to the contact to the PCB. The solenoid valves MV have important functions, in particular for levels 4 and 5, and are to be designed with redundant control of the drivers 20/20r, wherein the drivers also have an isolation switch. The contact to the circuit board PCB may likewise be of redundant configuration by way of a second contact on the connecting web 21, which is connected to a small circuit board PCB 22 with the second driver.
For cost reasons, it is advantageous to provide a 1-part circuit board PCB. For the case of an ingress of water, the circuit boards PCB may be separated by webs with seals in the housing of the open-loop and closed-loop control ECU with the two redundant circuits. Possible conductor track cracks are also advantageously covered or ruled out by redundancies. The remaining electronic connections of motor 26 to circuit board PCB 23 by means of electrical connection 15, of motor 2 to the electrical connection 16 of the motor of the pressure supply DV1, and those to rotation angle sensor 6, are also of importance. The advantage of parallel arrangement of pressure supply DV1 is the short length of the electrical connection.
For the above-described variants a to f, the following components may advantageously be of identical design:
- Pressure supply device DV1: for all variants a to f;
- Pressure supply device DV2: for all variants with redundant pressure supply;
- HCU/ECU: for the two variants without redundant pressure supply;
- Master brake cylinder HZ and travel sensor WS: separate and integrated with pedal sensors for five of the six variants, with the exception of variant f. without master brake cylinder. Separate master brake cylinder HZ but with additional reservoir VB.
- Solenoid valve MV: for all variants
- Motor sensor: for all variants.
Aside from the electric pedal corresponding to system f., all components are modular. The manufacturer and user thus have a modular system (OEM) an excellent basis inter alia for minimizing costs.
The abovementioned unit has the 2-circuit reservoir VB with float and level sensor NS, which may be integrated in the central open-loop and closed-loop control unit ECU. This level sensor NS should likewise be of redundant configuration and continuously measure the level, because a loss of volume owing to a leak is quickly detected in this way. Since, in this case, the connection to the master brake cylinder HZ is omitted, and thus the fall-back level with respect to the master brake cylinder HZ in the event of the failure of both pressure supply devices DV1 and DV2 and/or of the on-board electrical system is also omitted, the valves BP1 and BP2 are preferably designed as valves which are closed when electrically deenergized.
One important component of an electromotive drive is the motor sensor 34 for the electronic commutation and control of the position of the piston. The motor may be combined with different types of drive, for example transmission, trapezoid or spindle 57 with ball screw drive 58, as shown in
Different types of sensors, such as segment sensors with inductive or magnetic-field-sensitive sensors, may be used, or else sensors that are arranged on the motor or transmission axis. These sensors are particularly simple in terms of construction and are composed of a sensor target, for example in the form of a two-pole or multi-pole magnet, and a magnetic field-sensitive sensor element, for example in the form of a Hall sensor, GMR sensor, or the like. This sensor element 34 is electrically connected to the electronic control unit ECU, which is mounted either directly or via an intermediate housing on the motor. The sensor element 34 is preferably arranged in a sensor housing composed of an outer housing part 52 and an inner housing part 52a, which together accommodate inter alia a circuit board 22, on which the sensor element 34 may be arranged.
According to the invention, an elastic part 61 is in order to manage the various installation tolerances between housing 18 of the electronic control unit ECU, the motor housing 62 and possibly also an intermediate housing (not illustrated) and the sensor housing 52/52a. In the extreme case, it is necessary here for tolerances in all three directions x, y, z to be compensated. This is achieved according to the invention by means of a corresponding construction and fastening of the sensor housing to the housing 18 of the electronic control unit ECU and to the motor housing. Here, the sensor housing is advantageously divided into two parts, an outer housing 52 and an inner housing 52a, wherein the housing parts 52, 52a are connected to one another by means of conventional connection techniques such as welding or adhesive bonding and are preferably manufactured from plastic. The sensor housing is furthermore fastened to the motor housing 62, preferably in two places. The sensor circuit board 22 is flexible in the upper part to the plug connector strip in order to manage the above-stated tolerances. A flex PCB (flexible circuit board), for example, is suitable for this. The electrical connection 22a from this flexible circuit board 22 to the main circuit board 23 of the electronic control unit ECU is preferably realized by means of the particularly fail-safe plug connector 51 with press-fit contacts. For assembly with the main circuit board 23, the housing 18 of the electronic control unit ECU has an aperture with a lid.
The sensor housing 52, 52a is connected and fixed to a projection of the ECU housing 18. Situated in between is an elastic part 61, which may for example be a flexible elastic seal or a seal bellows. The elastic part is preferably designed as a lip seal. This flexible and elastic seal 61 thus serves for 3-axis tolerance compensation. The electrical connection from the motor winding to the circuit board 23 is realized by means of a conventional plug-in contact.
This sensor arrangement illustrated in
- HZ Master brake cylinder (single)
- aHZ Main axis of the master brake cylinder
- aDV1 Axis of the first pressure supply device DV1
- a1DV2 Horizontal orientation of the axis of the second pressure supply device DV2 perpendicular to the axis aDV1 of the first pressure supply device DV1
- a2DV2 Vertical orientation of the axis of the second pressure supply device DV2 perpendicular to the axis aDV1 of the first pressure supply device DV1
- DV Pressure supply
- HCU Hydraulic control unit
- ECU Electronic computing unit
- ECU-V Front side of the ECU
- ECU-S Side wall of the ECU
- ECU-O Top side of the ECU
- ECU-H Rear side of the ECU, facing the bulkhead of the vehicle
- PI Pedal interface
- SW/H Bulkhead/bracket
- St Plug connector
- BKV Brake force booster
- NS Level sensor
- RZ Wheel cylinder
- MV Solenoid valve
- Dr Throttle
- SV Suction valve of pressure supply device DV1
- A Housing for HCU and pressure supply device DV1 and optionally
- pressure supply device DV2
- A1 Partial housing for HCU and DV2
- A2 Partial housing for pressure supply device DV1
- B Housing for ECU
- C Housing for master brake cylinder HZ and travel simulator WS with flange
- aDV1 Motor axis of DV1
- aDV2 Motor axis of DV2
- aHZ Longitudinal axis of master brake cylinder HZ
- VB Reservoir
- VBH Rear region of the reservoir
- VBM Central region of the reservoir
- VBV Front region of the reservoir
- 1 Pedal plunger
- 2 Motor
- 3 Intermediate housing
- 4 Fastening screw
- 5 Sensor housing
- 6 Rotation angle sensor
- 7 Closure lid
- 8 Piston
- 9a/9b Connections to the reservoir VB
- 10 Connections to the wheel cylinder RZ
- 11 Connection to the master brake cylinder HZ
- 12 Flange of master brake cylinder HZ
- 13 Fastening screw
- 14 Fastening screw to bulkhead or bracket
- 15 Electrical connection motor between pressure supply device DV2 and ECU
- 16 Electrical connection of pressure supply device DV1 motor
- 17 Electrical connection of rotational angle sensor
- 18 ECU housing
- 19 Web with seal
- 20 Driver for solenoid valve MV
- 21 Connection web of solenoid valve MV
- 22 Small PCB
- 22a Electrical connection of the main PCB to the PCB 22 of the ECU
- 23 Main PCB
- 24 HCU block
- 25 Bore for eccentric piston pump DV2
- 26 Motor for pressure supply device DV2
- 27 Outline contour 8″, vacuum brake force booster BKV
- 28 Stop ring for piston
- 29 Line to the reservoir VB
- 30 Force-travel sensor KWS
- 31/31a Pedal rod
- 32 Spring housing
- 33 Master brake cylinder (HZ) piston
- 34 Sensor element
- 35 Target
- 36 Drive shaft
- 37 Toothed gear
- 38 Toothed rack
- 39 Guide part
- 40 Guide rail
- 41 Target
- 42 Inductive sensor
- 43 Master brake cylinder (HZ) housing
- 44 Travel sensor (WS) piston
- 44a Travel sensor (WS) spring
- 45 Travel sensor (WS) seal
- 46 Slide ring
- 47 Connecting bores travel sensor (WS)-master brake cylinder (HZ) and HCU block 24
- 48 Slide rings
- 49 Bearing part
- 50 Resetting spring
- 51 Plug connector strip with press-fit contacts
- 52 Sensor housing 1
- 52a Sensor housing 2
- 53 Measurement flange
- 54 Closure plug
- 55 Fastening, sensor housing
- 56 Threaded nut
- 57 Threaded spindle
- 58 Ball-screw drive KGT
- 59 Piston
- 60 Motor contact to ECU
- 61 Housing seal
- 62 Motor housing
- 63 Motor bearing
- 64 Rotor
- 100 Opening of the reservoir
- 101 Closure lid of the reservoir
- 152 Closable opening
Claims
1. An actuating device for a hydraulically acting brake system, comprising the following components: wherein the brake system has at least two hydraulic circuits, and wherein a pressure change is enabled to be performed by means of the pressure supply device in at least one wheel brake assigned to one of the hydraulic circuits, wherein the valve arrangement and the at least one piston and pressure chamber of at least one of the one or more pressure supply devices are arranged in a first housing or, when assembled, form a unit or module, and wherein the housing of the actuating device is hydraulically connected to the first housing or to the unit or the module.
- a master brake cylinder which is arranged in a housing, and which has at least one piston enabled to be acted on with force by an actuating device in the form of a brake pedal,
- one or more pressure supply devices, wherein at least one of the pressure supply devices is a piston-cylinder unit driven by an electromotive drive or is a double-action piston pump driven by an electromotive drive, wherein the electromotive drive is arranged to adjust the piston of the piston pump or double-action piston pump directly or via a transmission gear,
- particular a recirculating ball gear,
- at least one valve arrangement with solenoid valves,
- at least one electronic open-loop and closed-loop control unit,
2.-65. (canceled)
Type: Application
Filed: Mar 21, 2019
Publication Date: May 19, 2022
Patent Grant number: 12227151
Inventors: Thomas LEIBER (Rogoznica), Heinz LEIBER (Oberriexingen)
Application Number: 17/429,527